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Post-translational modifications at the ATP-positioning G-loop that regulate protein kinase activity
1Department of Pharmacology, College of Physicians and Surgeons, Columbia University, 630 West 168th Street, New York, NY 10032, USA.
Pharmacological Research
|July 27, 2018
Summary
Protein kinases regulate cell functions via their conserved catalytic core. This review explores how post-translational modifications in the glycine-rich loop (G-loop) impact protein kinase activity and cellular processes.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Biology
Background:
- Protein kinases are crucial enzyme superfamilies regulating cellular functions.
- They possess a conserved catalytic core with a highly flexible glycine-rich loop (G-loop).
- The G-loop binds ATP, positioning it for phosphotransfer.
Purpose of the Study:
- To review literature on post-translational modifications (PTMs) in or near the G-loop of protein kinases.
- To highlight the functional significance of these PTMs in kinase regulation.
- To explore how PTMs influence enzyme activity and cellular roles.
Main Methods:
- Literature review of scientific publications.
- Analysis of conserved regions within protein kinase structures.
- Examination of PTMs in the glycine-rich loop and adjacent residues.
Main Results:
- The G-loop's consensus GxGxxG sequence is critical for ATP binding.
- Residues flanking the G-loop triad are common targets for phosphorylation and other PTMs.
- Inhibitory phosphorylation of cyclin-dependent kinases (CDKs) in this region regulates cell cycle progression.
Conclusions:
- PTMs in or adjacent to the G-loop are critical regulators of protein kinase activity.
- These modifications influence diverse cellular functions beyond ATP binding and phosphotransfer.
- Understanding G-loop PTMs offers insights into kinase-mediated signaling pathways and disease.
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